The “Single-Edge Nibble Transmission” signal (SENT signal) is understood to be a signal which, for example, is used in the automobile field and in which only one type of edge, typically a falling edge, of the signal is considered. By means of a time interval between two falling edges, an information item is then transmitted.
When using SENT, it is normally necessary that many errors are detected by a receiver of the signal, for example data errors, which can be determined by means of a check code, e.g. by means of a cyclic redundancy check (CRC), frequency shifts, departure from a predetermined frequency range, dropping below a minimum distance or exceeding a maximum distance between two falling edges, exceeding or dropping below an expected number of falling edges, etc.
Usually, signal quality is not considered when an SENT signal is used. This can be based on an assumption that the signal is good (enough) if falling edges are detected at all. And between two falling edges, the signal would also have to have risen again.
If a signal quality is so poor that the falling edges are no longer present, a data error can be detected in a conventional manner.
However, a period between a falling edge and a subsequent rising edge can also be greatly shortened in the case of an SENT signal (also called low-signal period), for example almost negligibly short.
One cause of this can be that parameters of a data transmission device (which can have a transmitter and the receiver) become worse, e.g. contacts can corrode or become detached, or the like. A further cause can be that the system (e.g. deliberately) can be set in this way. In addition, the signal can pass through a low-pass filter in the receiver, which can additionally shorten the low-signal period. Furthermore, the signal can be subjected to further signal processing processes which can have an influence on a steepness of the edges and can thus shorten the low-signal duration.
Although the data transmission device, which can continue to develop a signal having a shortened period of time easily so that the signal no longer has any usable falling edges and thus becomes faulty, a classification of the signal and/or prediction and/or suppression of the error is currently not possible.
An examination of the signal with regard to a susceptibility to errors is not carried out, nor is it provided for.
When the error occurs (i.e. when the falling edges are missing), the signal receiver would find that falling edges are missing in data frames and discard the data frames.
A cause of the error would not be obvious during this event. As a result, difficult and/or expensive repairs in a workshop could appear to be necessary but after the repair the data transmission device overall can still be operated within a threshold range (for example, the contact can still be corroded) so that with only a slight deterioration of the signal-influencing parameters (which can still be within normal tolerances, for example), the data transmission can fail again.